This paper focussed on the development of a plasticity model to describe high rate deformations of metals. Modelling of target mechanical response was performed in frames of continuum mechanics. Plastic flow was described as the result of an over barrier dislocation sliding in specific slip planes. Computations of shock wave propagation in face-centered cubic, body-centered cubic and hexagonal close-packed metals modelling in comparison with shock wave experiments were performed to verify the model. The model predicts yield strength increase on elastic precursor in aluminium monocrystal and titanium of high purity at high temperatures. The action on a copper target of the electron beams with energy density (the total energy incident on an unit area during an irradiation pulse) 8.6J/cm2 and varied pulse duration was investigated. At the considered irradiation regime the target remained in a solid state (maximal temperature was 710K) and shear stresses could reach values of about 0.72GPa. Depth distribution of dislocation density after irradiation had a maximum that was localized on a distance of 10μm from the irradiated surface and the maximum dislocation density was about 6 x 109/cm2 in the target. The shortening of the exposure time to 1 ns led to the increase of the dislocation density. Further reduction of exposure time had a weak effect on the dislocation density because the shear stresses reach a limit.

Dislocation Based High-Rate Plasticity Model and Its Application to Plate-Impact and Ultra Short Electron Irradiation Simulations. V.S.Krasnikov, A.E.Mayer, A.P.Yalovets: International Journal of Plasticity, 2011, 27[8], 1294-308